Combination-square.



1-r 3.839,1a2; l l. y PATENTEDEC. 25;,1906. l.

l J/MOLBAN@ `G0MBINATI0N SQUARE.

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, squares of the type disclosed in United J UNITEDSTATES PATENT OFFICE. e y JOHN, mums, ALABAMA. y l. y, k CMBlNATioN'fsouAnEr; i

I No. 839,132@ j specication.

'This invention relates to combination- States Patent No.L 535,717,r granted to yme proceeds, the invention resides inthe com#` 'fbination and arrangement of parts land in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of invention herein disclosedcan be made within the scope of the following claims without departingfrom the spiritfofythe yinvention or sacri# ficing any of its advantages'. y f In the accompanying drawings, forming part of this specification, Figure 1 is a side ele`- y vation of a combination-square,constructedf in accordance with vthe invention. Fig. `2 is -K an enlarged detail view showing the upper end of the stock. rFig'. 3 is a transverse section through the sight-opening.

Like reference numerals indicate corre-l sponding'parts inthe different igures ofthe The-improved combination-.square of this invention comprises ,a stock 1, whichis formed adjacent itsupper end with a circular sight-opening2- j The sight-opening 2 serves to produce aty theup'per end of the stock 11a web 3, across whichl extends an index-line 4. The reference numeral 5 indicates the pivot-point ofv a main blade 6, which'is` connected with the lower end of the: stock 1, as shown/The mainbl'ade 6is formed with a slot7, which is concentric withthe pivotpoint y5l and isadapted to receive theshank of an adjusting-screw 8, which extends through the stock 1as shown. yBy loosen-r ing` the adjusting-screw 8 the main blade 6 can be moved pivotally upon the stock 1 and clamped in adjusted positionby Itightening the adjusting-screw 8.Vv Above the concentric slot 7 the main blade 6 is provided with an ordinary scale or graduation 9, which is .Specification of Letters Patent. Application led July 21, 1906. Serial No. 327,204.

' Patented Dec. 25,1906.

concentric to the pivot-point and is adaptedfto be read at the lower end of the indexline 4 through the sight-opening 2 when the main blade is moved pivotallyupon the stock. Above the ordinary scale 9 the main e blade 'is provided with what I shall vterm a main blade can be readily adjusted upon the stock-and adapted for the proper marking of rafters `and the like.

` ."raftenscale 10, which contains certain marks or graduationsfby means of which the The rafter-scale" 10 adapted tobe read at the'upper end of the index-line 4, as will be apparent. The pro- -visionof thesight-opening 2, which forms the web 3, adapted to receive the index-line "4, constitutes a valuable improvement over the construction'shown in my former patent, aslthe index-line can be inexpensively placed lupon the web and when so placed will not be in danger of defacement or removal,

.whereas the pointer containedin my former construction was liable to become bent or vdisplaced'if the tool should` receive Vrough treatment.

The main blade 6 is provided along its youter edge 11 andrupperedge 12 with what I shall term a polygon-scale, in that by means of the stock 1 and main blade 6, to-

gethery with the polygon-scale, the diiierent radial lines ofI an Octagon or other geometrical gurecan be readily calculated.

'.The -main blade 6v is provided with an integral Vextension-blade 14, which projects' through a suitable slot in V4the stock 1 and is adapted to be used in conjunction with said stock for securing `different angles. The blade 14 preferably is provided with a series of perforations 15, adapted to receive a nail or other pointed instrument to act as a centerfvor pivot-so ,that when a pencil-point is passed through the pencil-opening 16 in the stock'l the combination-square can be used for drawing a circle.

From the foregoing description it is beexpensive in construction, as well as thoroughly efficient 1n operation.

What is claimed 1s-1- l i 1'. A combination square, comprising a stock havingv at its upper end a sight-opening forming a web, said web being provided roo` IIC

i adapted to be read at the other end of said .index-line, an extension-blade connected .connected with the lower end of t e stock one end ofsaid index-line, a rafter-scale on 'said main blade.

with an index-line extending thereacross, one end of said index-line terminating at the upper end of the Stock and the other end of said index-line terminating at the upper part kof the sight-opening, a main blade ivotally and having a slot concentric to the pivotpoint of the blade, said main blade being provided with an ordinary scale concentric to'its pivot-point and adapted to be read at' the blade concentric to its pivot-point and with the upper portion of said main blade and extending through a, slot in saidstock7 and an adjusting-screw extending through the stock and through the concentric slot in -be read at the ot polygon-scales extending along the outer and ing at the upper end of the sight-opening, a main blade ivotally connected with the lower end of t e stock and havin a slot concentric to the )ivot point thereo said blade being provided with an ordinary scale concentric to its pivot-point and adapted to be read through said sight-opening' at one end of said index-line, a rafter-Scale on the blade concentric to its `votjpoint and adapted to 1lier end of said index-line,

u per edges of said main blade, an extensionb ade connected with the upper portion oi' said main blade and extending through a slot in said stock, and an adjusting-screw extending through the ystock .and through the concentric Slot in said main blade.

In testimony that I claim the foregoing as 'my own I have hereto alixed my signature in the presence of two Witnesses.

JOHN MCLEAN. 

